CanCOLD Visit 1 subject demographic, pulmonary function and imaging measurements
| Parameter (±sd unless specified) | At-risk (n=316) | No COPD at follow-up (n=260) | COPD at follow-up (n=56) | p-value |
| Subject demographic | ||||
| Age, years | 65 (9) | 65 (9) | 65 (10) | 0.91 |
| Female sex, n (%) | 126 (40) | 107 (41) | 19 (34) | 0.37 |
| Caucasian, n (%) | 300 (95) | 248 (95) | 52 (93) | 0.50 |
| Pack-years, years | 18 (19) | 18 (19) | 22 (19) | 0.053 |
| BMI, kg·m−2 | 28 (5) | 28 (5) | 27 (5) | 0.29 |
| Height, cm | 168 (9) | 168 (9) | 168 (10) | 0.87 |
| Current smoker, n (%) | 64 (20) | 47 (18) | 17 (30) | 0.04 |
| Pulmonary function | ||||
| FEV1, %pred | 99 (16) | 99 (16) | 96 (17) | 0.16 |
| FVC, %pred | 97 (16) | 96 (15) | 98 (17) | 0.32 |
| FEV1/FVC, % | 77 (5) | 78 (5) | 73 (3) | <0.0001 |
| FEF25–75, L | 2.46 (1.01) | 2.56 (1.05) | 1.96 (0.55) | <0.0001 |
| RV, L | 2.27 (0.57) | 2.22 (0.54) | 2.54 (0.62) | 0.0005 |
| TLC, L | 6.14 (1.28) | 6.07 (1.25) | 6.48 (1.39) | 0.049 |
| RV/TLC, % | 37 (7) | 37 (7) | 40 (8) | 0.02 |
| DLCO, %pred | 111 (23) | 112 (24) | 109 (20) | 0.67 |
| Symptoms | ||||
| CAT score | 5.9 (5.1) | 6.0 (4.9) | 5.4 (5.9) | 0.07 |
| SGRQ, total | 9.2 (11.0) | 9.5 (11.2) | 10.4 (14.2) | 0.61 |
| MRC | 1.3 (0.5) | 1.2 (0.5) | 1.4 (0.7) | 0.21 |
| Imaging | ||||
| TLV, L | 4.48 (1.08) | 4.40 (1.05) | 4.84 (1.19) | 0.005 |
| TAC, n | 213 (65) | 218 (66) | 193 (59) | 0.01 |
| LAA910, % | 19 (11) | 18.7 (11.0) | 21.9 (13.3) | 0.16 |
| LAA950, % | 2.9 (3.1) | 2.9 (3.1) | 3.3 (2.9) | 0.15 |
| Pi10, mm | 3.93 (0.14) | 3.96 (0.15) | 3.96 (0.13) | 0.51 |
| Wall area percent, % | 65.3 (2.6) | 65.3 (2.5) | 65.4 (2.8) | 0.62 |
| LAA856, % | 18 (15) | 18 (15) | 20 (15) | 0.25 |
BMI: body mass index; FEV1: forced expiratory volume in 1 s; %pred: percent predicted; FVC: forced vital capacity; RV: residual volume; TLC: total lung capacity; DLCO: diffusing capacity for carbon monoxide; TAC: total airway count; LAA950: low attenuation area of the lung with attenuation values below −950 HU on full-inspiration CT; Pi10: the square root of the airway wall area for a theoretical airway with 10 mm internal perimeter. Significance of difference : p<0.05.